Noise reduction device of hydroelectric generating set

The noise reduction device comprises an outer box body and a box door, an inner box body is slidably installed in the outer box body through a first guide structure, two sets of symmetrical rectangular inner grooves are formed in the inner wall of one side of the outer box body, sliding blocks are slidably installed in the rectangular inner grooves, and the sliding blocks are slidably installed in the sliding blocks. A hollow rectangular-ambulatory-plane sound insulation frame is fixed to the surface of the sliding block, a sound insulation structure is slidably installed in the hollow rectangular-ambulatory-plane sound insulation frame, the top end of the sound insulation structure is slidably connected with the top of the inner box body through a second guide structure, and a gear transferring structure used for driving the inner box body to ascend and descend is installed on the inner wall of one side of the outer box body. The device can be assembled and used according to hydroelectric generating sets of